Due to the recent widespread use of networks, such as the Internet, the purchasing of various goods (or following certain procedures for purchase) on networks is becoming common. There are various goods that can be purchased on a network, for example, not only tangible goods but also intangible goods. Intangible goods include, for example, music data and video data.
Some intangible goods can be obtained not only by being purchased, but also by being rented. Regardless of whether the user purchases or rents intangible goods, he/she can purchase desired content data, such as music data or video data, by using a computer at home without the need to go to music stores or rental stores for compact discs storing content data.
Unlike tangible goods, the intangible goods can be easily copied, and undesirable actions may occur, for example, copies of the intangible goods may be delivered from one purchaser to other persons. Generally, a mechanism for preventing such undesirable actions is contained in intangible goods.
For example, data concerning licenses (usage rights) is provided (sent) together with content data. By using such license data, the playback operation of content data provided to the user is managed, thereby preventing undesirable actions, such as copying.
When the user wishes to purchase content data via a network, he/she first accesses a site handling the content data via the network, and performs processing for purchasing the content data, such as inputting predetermined information, according to instructions from the site.
After completing the processing for purchasing the content data, the content data is downloaded from the site to a user device via the network. The downloaded content data is stored in a recording medium, such as a hard disk drive, in the device, together with license data.
After being downloaded to the user device, the license data is associated (bound) with ID information unique to the device storing the content data. Because of this association, even if the content data is copied, it can be prevented from being played back in a device other than the device which has downloaded the content data, i.e. a device that cannot associate its ID information with the license data.
In this manner, content data is downloaded to a device in which purchase processing was performed and is played back by this device. Accordingly, when the user purchases content data by using a device other than a device at home when he/she is away, he/she cannot play back the purchased content data by using the device at home.
In other words, the user cannot perform processing for storing desired content data in the device at home by using a different device when, for example, the user is away from home. Accordingly, the user cannot purchase content data by using a device different from the device used for playing back the content data.